#include "types.h"
#include "riscv.h"
#include "defs.h"
#include "date.h"
#include "param.h"
#include "memlayout.h"
#include "spinlock.h"
#include "proc.h"
#include "sysinfo.h"


uint64
sys_exit(void)
{
  int n;
  if(argint(0, &n) < 0)
    return -1;
  exit(n);
  return 0;  // not reached
}

uint64
sys_getpid(void)
{
  return myproc()->pid;
}

uint64
sys_fork(void)
{
  return fork();
}

uint64
sys_wait(void)
{
  uint64 p;
  if(argaddr(0, &p) < 0)
    return -1;
  return wait(p);
}

uint64
sys_sbrk(void)
{
  int addr;
  int n;

  if(argint(0, &n) < 0)
    return -1;
  addr = myproc()->sz;
  if(growproc(n) < 0)
    return -1;
  return addr;
}

uint64
sys_sleep(void)
{
  int n;
  uint ticks0;

  if(argint(0, &n) < 0)
    return -1;
  acquire(&tickslock);
  ticks0 = ticks;
  while(ticks - ticks0 < n){
    if(myproc()->killed){
      release(&tickslock);
      return -1;
    }
    sleep(&ticks, &tickslock);
  }
  release(&tickslock);
  return 0;
}

uint64
sys_kill(void)
{
  int pid;

  if(argint(0, &pid) < 0)
    return -1;
  return kill(pid);
}

// return how many clock tick interrupts have occurred
// since start.
uint64
sys_uptime(void)
{
  uint xticks;

  acquire(&tickslock);
  xticks = ticks;
  release(&tickslock);
  return xticks;
}

// my trace
uint64
sys_trace(void){
  // 拿到mask
  int mask;
  if(argint(0, &mask) < 0)  return -1;
  
  // 将mask赋值给当前进程的mask属性 方便与syscall.c中的syscall函数共享属性 
  myproc()->mask = mask;
  // printf("hello!\n");
  return 0;
}

// my sysinfo
uint64
sys_sysinfo(void){

  // 获取第一个参数(指针地址)
  uint64 arg;
  if(argaddr(0, &arg) < 0) return -1;

  // 创建一个sysinfo结构体 并计算所需的三个信息
  struct sysinfo Sysinfo;
  Sysinfo.freemem = get_freemem();
  Sysinfo.nproc = get_nproc();
  Sysinfo.freefd = get_freefd();

  // 将sysinfo结构体写入用户空间的目标地址
  if(copyout(myproc()->pagetable, arg, (char *)&Sysinfo, sizeof(Sysinfo)) < 0) return -1;

  return 0;
}